Xamarin binding many entrys texts for each element of array - xamarin

Question

I'm programmatically creating entrys and programmatically trying to bind every entry text to appropriate array element (based on index). But it seems like it is not binding.
Trying to implement a mvvm. Can someone help with this problem?
This is a view part:
var saveMeasurmentViewModel = new SaveMeasurementViewModel();
BindingContext = saveMeasurmentViewModel;
var radius = Convert.ToInt32(DeviceDisplay.MainDisplayInfo.Width * 0.32);
var entryList = new List<Entry>();
for (int index = 0; index < 18; index++)
{
var entry = new Entry
{
Placeholder = (index + 1).ToString(),
TabIndex = index + 1,
};
object actualValueForBinding = saveMeasurmentViewModel.ActualValues[index];
entry.SetBinding(Entry.TextProperty, nameof(actualValueForBinding));
var frame = new Frame
{
Content = entry,
Margin = new Thickness(Math.Sin(20 * index * Math.PI / 180) * radius, 0, 0, Math.Cos(20 * index * Math.PI / 180) * radius),
};
entryList.Add(entry);
MainGrid.Children.Add(frame, 0, 2, 0, 1);
}
ViewModel property, that i'm trying to bind:
public double[] ActualValues
{
get { return actualValues; }
set
{
actualValues = value;
OnPropertyChanged();
}
}

Answer 1

In your case , you can't bind the text of entry to the list directly . It would be better to use BindableLayout
in xaml
<ScrollView Orientation="Both">
<StackLayout BindableLayout.ItemsSource="{Binding ActualValues}" x:Name="MainGrid" HorizontalOptions="Center"
VerticalOptions="CenterAndExpand">
<!-- Place new controls here -->
<BindableLayout.ItemTemplate>
<DataTemplate>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
</Grid.RowDefinitions>
<!--Margin="{Binding Margin}" you can also set margin with data-binding -->
<Frame Grid.Row="0" Margin="10,10" WidthRequest="90" HeightRequest="50" BackgroundColor="LightBlue">
<Entry TabIndex="{Binding Id}" Text="{Binding Value}" WidthRequest="80" HeightRequest="30" TextColor="Red" />
</Frame>
</Grid>
</DataTemplate>
</BindableLayout.ItemTemplate>
</StackLayout>
</ScrollView>
in Viewmodel
public class MyModel:INotifyPropertyChanged
{
public MyModel(int id)
{
Value = "entry" + id.ToString();
Id = id;
var radius = Convert.ToInt32(DeviceDisplay.MainDisplayInfo.Width * 0.32);
// Margin = new Thickness(Math.Sin(20 * id * Math.PI / 180) * radius, 0, 0, Math.Cos(20 * id * Math.PI / 180) * radius);
}
public event PropertyChangedEventHandler PropertyChanged;
public Thickness Margin { get; set; }
public int Id { get; set; }
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
string _value;
public string Value
{
get
{
return _value;
}
set
{
if (value != _value)
{
_value = value;
OnPropertyChanged("Value");
}
}
}
}
public class SaveMeasurementViewModel : INotifyPropertyChanged
{
public event PropertyChangedEventHandler PropertyChanged;
public ObservableCollection<MyModel> ActualValues { get;set; }
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
public SaveMeasurementViewModel()
{
ActualValues = new ObservableCollection<MyModel>() { };
for (int index = 0; index < 18; index++)
{
ActualValues.Add(new MyModel(index) );
}
}
}
For more details you could check https://learn.microsoft.com/en-us/xamarin/xamarin-forms/user-interface/layouts/bindable-layouts